Fire App Builder version 1.0.2 was released today (see https://github.com/amzn/fire-app-builder). The main feature includes the ability to send recommendations to the "Recommended By Your Apps" row on the Fire TV home screen.
Here are the release notes: https://developer.amazon.com/public/solutions/devices/fire-tv/docs/fire-app-builder-release-notes-version-1-0-2
